AVS 51st International Symposium
    Organic Films and Devices Wednesday Sessions
       Session OF+EM-WeM

Invited Paper OF+EM-WeM1
Self-assembled Monolayers in Organic Electronic Devices

Wednesday, November 17, 2004, 8:20 am, Room 304C

Session: Molecular and Organic Films and Devices - Electronics
Presenter: G. Horowitz, ITODYS, University Denis Diderot, France
Authors: G. Horowitz, ITODYS, University Denis Diderot, France
P. Lang, ITODYS, University Denis Diderot, France
W. Kalb, RWTH Aachen, Germany
M. Mottaghi, ITODYS, University Denis Diderot, France
A. Roumiantseva, ITODYS, University Denis Diderot, France
A. Yassar, ITODYS, University Denis Diderot, France
Correspondent: Click to Email
The use of molecular materials as active component in electronic devices has recently experience considerable interest. Organic electronic devices are fabricated by piling up several layers on top of each other. Because of that structure, the role of interfaces is crucial in the performance of the devices. An elegant way of controlling the quality of interfaces is the use of self-assembled monolayers (SAMs), which consists of a single layer of molecules chemisorbed on a surface. The molecules are most often based on long alkyl chains that tend to self-assemble to form highly ordered single layers. One end of the chains is substituted with a group capable of inducing chemisorption on the surface, while the other end can be used to control the quality of the modified surface. This technique will be exemplified by two approaches. The first one is a transistor made of a thin film of pentacene deposited on an alumina layer that serves as the gate dielectric. We show that the performance of the transistor is strongly influenced by the modification of the alumina surface by a SAM of a fatty acid. Correlation is made between the structure of the pentacene film and the properties of the transistor. In the second example, the SAM is made of hybrid molecules comprising an alkyl chain connected to a conjugated part (e.g., thiophene or acene). In that case, the SAM constitues the very heart of the device, which may open the way to electronics at the molecular level.